Oil-cooled transformer



May 4,1926.

R. V. BINGAY OIL COOLEDTRANSFORMER Original Filed June 2. 1920 ZEW/ 5 973 A TTEigY/S Patented May 4, 1926.

UNITED S-TATQES'YPATENT OFFICIE.

ROBERT V, IBINGAY,- OR PITTSBURGH, TENNSYLVANIA, ASSIGNOR TO PITTSBURGH TRANSFORMER COMPANY, A CORPORATION OF PENNSYLVANIA.

OIL-COOLED TRANSFORMER.

Original application filed June 2, 1920, Serial mi. 386,115. Divided and this application filed wow 11,1921. Ser1a1'No.507,12'1.

Cooled Transformers, of which the following is a specification.

This invention relates to electrical transformers and particularly to transformers cooled by the circulation of oil in a tank, and this application is a division of prior application, Serial No. 386,115, filed June 2, 1920,

The chief object of the invention is to provide a transformer and tank construction that is inez pensive and strong and adapted to provide -for the efiicient circulation-of the cooling oil. 1

The transformer tank is preferably formed of sheet steel and further objects of the invention particularly in the method of relatively supporting the transformer and tank will appear from the following description taken in connection with the accompanying drawings in which Fig. 1 is a vertical sectional elevation of a transformer illustrating a specific embodiment of the invention,

Fig. 2 is a perspective view of a portion of in place on its base, and I Figs. 4 and 5 are detail sectional vlews on enlarged scale.

tion shown in Fig. 1 a transformer T, for instance of the double magnetic circuittype, is

supported in frame work F resting on the bottom M of tank K. The tank K stands on the base B and has a cover C fastened to its top by clamps 20. Bolts 0 extending upward from the frame F pass through the cover C and have their ends enclosed by air tight caps 21. The cover C also carries the Y depth dependent upon the size of the tankand the relative cooling surface. required.

Hitherto the depth of these'sider corrugathe tank body illustrating .its formation, F igi3 is a vertical elevation of the tank In the specific embodiment of the inven-' .along this line.

tions has been limited by considerations of strength and the difliculty and expense of produclng deep corrugations. The shallower corrugations give a correspondingly restricted cooling surface and often it has been necessary to resort to extra cooling pipes or circulating means where the available air if properly provided for. In the tank of this invention corrugations of the tank body may be of any desired depth and strength required by practice and at the same time these corrugations are formed from sheet metal plates in a siniple and inexpensive manner ends of the inner corrugations 28 as indicated at 39. The end edges of these corrugations are thus flattened out into substantially straight lines as indicated at 38 and the ends of the corrugations are spread 50' as to be brought toward and finally into contact-with each other as indicated at 4:0 and 41. v The edges of the intermediate portion 30 and the outer bends 29 are also hammered over and brought into contact along line 42 and welded. securely together The hammering outward of the ends of the corrugations 28 forms the inclined flattened surfaces 39 and brings the extreme ends of these surfaces substantially into the line of the corners 32 of the notches 24, forming a continuous annular ridge around the end of the tank from which the corrugations incline in opposite directions. This gives a stron arched construction terminatingv in a solid continuous apex '01.

peak; the end of each corrugation is arched with a central heavily welded seam, and all these arches of the corrugations converge to the top: ring so that these corrugations are not only strong in themselves but reinforce and mutually sustain each other through their common connection. Alllvertical seccooling of the tank itself will be sufficient I tions through this strli cture show a characteristic arched form and all horizontal sections also show continuous corrugations with arched connecting bends, and with a tank constructed according to the method of this invention it is possible to use a verylight gage of sheet steel.

Thetwo ends of the tank body are substantially identical and comprise a corrugated cylinder with the corrugations 1nclined and arched at each end and rigidly welded to a continuous annularend portion at each endi This tank body is very strong, irrespective of its connection with the bottom and cover pieces. At each end it provides an annular beveled surface formed by the ring of inclined flattened surfaces 39 and this beveled surface serves for the attachment of the bottom and top pieces in a simple and very rigid manner. When the bottom and top pieces are in place, as herein after described, this strong tubular portion reinforces the end portions in such manner that each part is trussed againstthe other to receive the strains put upon the tank.

The bottom M of the tank is fornied by a circular plate, preferably of rolled. steel,

with its edge flanged upwardly at an angle (Figs. 1 and 4) and this edge flanget5 of the bottom M is nearly at right ang es to the beveled surfaces 39 and is just fittedizo an intermediate portion of these surfaces. With the bottom piece M assembled and clamped in place a heavy weld 46 is made in the corner between the surfaces '39 and the flange so that the bottom surface of the tank is below the surface of this weld which will therefore be held spaced from the base' 13 of the transformer. in finally assembled position. This fianging of the bottom plate M gives this plate an arched construction and protects it against warping due to the heat of the welding operation and "duetoi any strains on it in service, and this arching at the bottom also holds the welded seam away from contact with the base or other surfaces so that this seam does not collect moisture and become rusty or weaken or wear in use. This construction permits the bottom plate and the top ring, or either, to be made either thicker or thinner than the metal in the tank body, or of the same thickness as may be most advantageous. 4

The top of the tank body has welded to it the steel or iron angle ring 50, formed by iplling an angle into circular form with its flange 51 inclined at substantial] y the an le of the tank cover C and the ends of the circle welded together. This ring is sized to fit into the top of the tank and engagean intermediate portion of the beveled surfaces 39 at the top and is fastened in place by heavy welding 52 all'around in the annular corner between the surfaces 39 and ring 50. This ring forms additional rein- M is crowned as shown and fastened to the ring 50 by clamps 20 with gasket 53 between the cover and the ring. This cover is provided with the central flanged opening 55 and with terminal insulatorsN' and N for the leads. The bolts 0 of the frame F pass through this'cover and are adapted to have eyes screwed on their upper ends for lifting the frame F and transformer'l out of the tank the cover being lifted with the transformer and the clamps 20 having been released. ,Underneath'the cover C the bolts 0 carry nuts lUbea-ring against the under surface of the cover and adjusted on the bolts to press u ward on the cover and causing screw rods to thrust downward on the frame F standing on the bottom M of the tank when the clamps 20 are fastened in place. The weight of the transformer parts therefore is not carried by the tank sides on base B. Projections 63 are resting g to the edges of the tank cover and welde 1 through these holding bolts 64 pass to the has an upward pull-transmitted'to its upper end by cover C, clamps 20 and angle ring 50.

The tank body is merely a light housing supported on the transformer and serves therefore simply as a casing for containing and cooling the oil with which it isfilled.

In accordance with this invention provide guide vanes for separating the rising and descending currents of oil comprising guidingsurfaces adjacent the inner bending of the corrugations, and. for this purpose i have shown an inner bafile cylinder just within the bends 29.- The'columns of cooled but is transmitted. directly to the bottom M oil in the corrugations are relatively heavy and pass down rapidly thro h th 801.1%

gations, drawing'in at the top the heated of the oildown through the corrugations distributes the heated 011 over a larger area of,

downward through the pipes formed by the,

corrugations. The temperaturegradient at the sides therefore is much less abrupt and the cooling taking place over a much larger area is much moreeflicient.

-.Iclaim: 1. In a transformer construction, the combination with a tank having asheet nfetal bodyfrom the bottom to the top of the tank, of a transformer havin its frame supported on the sheet metal. ottom of said tank, a sheet metal cover for said tank, adjustable holding means between said cover g-and said frame, and means to clamp said cover upon said tank with said holding means pressing upward on'said cover and downward on said frame to hold said frame against the bottom of said tank and to assist in supporting the body of the tank.

'2. In a transformer construction, the combination with a transformer, ofa 'base, a housing surrounding said transformer and comprising a bottom member, sides and a 3 means to support said housing in assembled relation upon said transformer, said means comprising a frame for said transformer, and adjustable bolts between said frame and 3. The combination with a tank formed at its upper edge with a cover seat, a transformer in said tank, a yielding arched sheet metal cover-on said tank having its outer edge extending beyond said seat, means-between said transformer and cover adapted to press upwardly on said coverat points inwardly spaced from said seat and clamping means engaging said cover and causing the said cover to conform to said seat to form a tight joint therewith. s

4. In a transformer structure the combination with a transformer tank having a sheet metal body, an angle bar bent to ring form and fastened to the upper end of said body and providing an outwardly extending flange, a gasket on said ring, and a cover clamped at its outer edge on said gasket and formed of sheet metal in arched shape toward the center so as to yield to the clamping pressure at the edges to resiliently accommodate itself to the ring and gasket and form therewith a tight seal under the clamping pressure between the cover and ring while transmitting a downward pressure from said ring to a structure within the tank.

5. In a transformer construction the comremovable cover, all formed of sheet metal,-

cover affording support-to said cover indev bination with a transformer tank having a sheet metal body formed with longitudinal corrugations with arched ends meeting in a ridge around the end of the body, an angle bar bent to ring form and fastened tothe upper end of said body and providing an outwardly extending flange, a gasket on said ring, and a cover clamped at its outer edge on said gasket. and formed of sheet metal in arched shape so as to yield to the clamping pressure to resiliently accommodate itself to the ring'and gasket and form there- 'with a tight seal under the clamping pres-, sure between the cover and ring while transmitting a downwardpressure from said ring to" a structure Within the tank. v

6. A transformer tank comprising a body portion of corrugated sheet 'metal with the upper endsof the inner corrugations flattened to form an inclined surface, and a top ring formed by an angle rolled into cirpu'lar form andwelded at its meeting ends, the vertical side of the angle being Welded to the inclinedsurface of the body portionand the horizontal side of the angle form ing a cover supporting flange,-a transformer core on the base plate, a sheet metal cover resting on said cover supporting flanges,

means for clamping the cover to the flange, and supporting bolts extending from the transformer core'to exert upward pressure on the under side of the cover.

7 A transformer tank comprising a body' portion of corrugated sheet metal with the upper ends of the inner corrugations flattened tojform an inclinedsurface, and ax top ring formed by an anglev rolled into circular. form and welded atv its meetingends, the vertical side of the angle being weldedv to the-inclined surface of thebody portion and the horizontal side of the'angle forming a coversupporting flange, a transformer core-on the base plate, a sheet metal cover restingv on said cover supporting flanges, means for clamping the cover to the fiange,.supporting bolts extending from the tran'sformercore to exert upward pressure on the under side of the cover, a base on which the tank rests, and clamping rods outside the cover exertin 'pressure' from the I upper outer clrcumference of the cover to the base outside the tank 1 8. A tank having a side wall and a bottom of sheet metal, a cover adapted to be secured to the tank, a transformer on said bottom, a base and means to clamp said bottom between the base and the transformer, said means comprising an adjustable mem ber extending between said transformer and cover and an adjustable member extending between said cover and base.

9. .A tank comprising a bottom and wall both of sheet metal, a base, a cover for said tank secured to said base, a transformer in said tank spaced from said wall and ad justable holding means pressing upward on said cover and downward on said transtormer. v

10. The combination with a sheet metal tank and a transformer therein, means for clamping said transformer in position in said tank comprising means pressing downwardly on said transformer and adjustable means external to said tank, said adjustable means operating independently of the sides of said tank to press upwardly on said transformer,

11. An electrical apparatus consisting of a transformer and tank therefor having bottom and sides of sheet metal and a holding and supporting structure adapted to absorb strains incident to movement or use of said apparatus, said structure comprising a base, a cover for said tank, and connecting means between said base and cover and between said transformer and cover supporting the sides of said tank' from said transformer and holding said transformer downward towards said base. 1

12. An electrical apparatus consisting of a transformer and tank therefor having bottom and side walls of sheet metal and a hold sorb the strains' incident to movement or use of said apparatus, said structure comprising a base, members extending from said base above said tank, and connecting means between said members and said tank and said transformer adapted to exert a downward pressure on said transformer and an upward pull on the side walls of said tank.

13. An electrical apparatus consisting of a tank therefor having bottom and sides of sheet metal, a transformer on said bottom positioned substantially centrally thereof, and a holding and supporting structure adapted to absorb strains incident to move- .ment oruse of said apparatus, said structure comprising a base, a cover for the tank, adjustable means connecting said base and cover adapted to press-downwardly on said cover. and adjustable meansv adapted to press upwardly on said cover and downwardly on said transformer whereby the bottom of the tank is clamped, at its central portion only, between said transformer and base.

ROBERT v. BINGAYQ 

